Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/iio/buffer/Kconfig b/drivers/iio/buffer/Kconfig
index 338774c..63f265c 100644
--- a/drivers/iio/buffer/Kconfig
+++ b/drivers/iio/buffer/Kconfig
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
 #
 # Industrial I/O generic buffer implementations
 #
diff --git a/drivers/iio/buffer/industrialio-buffer-cb.c b/drivers/iio/buffer/industrialio-buffer-cb.c
index ea63c83..47c96f7 100644
--- a/drivers/iio/buffer/industrialio-buffer-cb.c
+++ b/drivers/iio/buffer/industrialio-buffer-cb.c
@@ -1,8 +1,5 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /* The industrial I/O callback buffer
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
  */
 
 #include <linux/kernel.h>
@@ -36,7 +33,8 @@
 static void iio_buffer_cb_release(struct iio_buffer *buffer)
 {
 	struct iio_cb_buffer *cb_buff = buffer_to_cb_buffer(buffer);
-	kfree(cb_buff->buffer.scan_mask);
+
+	bitmap_free(cb_buff->buffer.scan_mask);
 	kfree(cb_buff);
 }
 
@@ -74,9 +72,8 @@
 	}
 
 	cb_buff->indio_dev = cb_buff->channels[0].indio_dev;
-	cb_buff->buffer.scan_mask
-		= kcalloc(BITS_TO_LONGS(cb_buff->indio_dev->masklength),
-			  sizeof(long), GFP_KERNEL);
+	cb_buff->buffer.scan_mask = bitmap_zalloc(cb_buff->indio_dev->masklength,
+						  GFP_KERNEL);
 	if (cb_buff->buffer.scan_mask == NULL) {
 		ret = -ENOMEM;
 		goto error_release_channels;
@@ -95,7 +92,7 @@
 	return cb_buff;
 
 error_free_scan_mask:
-	kfree(cb_buff->buffer.scan_mask);
+	bitmap_free(cb_buff->buffer.scan_mask);
 error_release_channels:
 	iio_channel_release_all(cb_buff->channels);
 error_free_cb_buff:
diff --git a/drivers/iio/buffer/industrialio-buffer-dma.c b/drivers/iio/buffer/industrialio-buffer-dma.c
index b32bf57..90cf6e5 100644
--- a/drivers/iio/buffer/industrialio-buffer-dma.c
+++ b/drivers/iio/buffer/industrialio-buffer-dma.c
@@ -1,8 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright 2013-2015 Analog Devices Inc.
  *  Author: Lars-Peter Clausen <lars@metafoo.de>
- *
- * Licensed under the GPL-2.
  */
 
 #include <linux/slab.h>
diff --git a/drivers/iio/buffer/industrialio-buffer-dmaengine.c b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
index 2b5a320..bea4a75 100644
--- a/drivers/iio/buffer/industrialio-buffer-dmaengine.c
+++ b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
@@ -1,8 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright 2014-2015 Analog Devices Inc.
  *  Author: Lars-Peter Clausen <lars@metafoo.de>
- *
- * Licensed under the GPL-2 or later.
  */
 
 #include <linux/slab.h>
diff --git a/drivers/iio/buffer/industrialio-triggered-buffer.c b/drivers/iio/buffer/industrialio-triggered-buffer.c
index d3db1fc..cb322b2 100644
--- a/drivers/iio/buffer/industrialio-triggered-buffer.c
+++ b/drivers/iio/buffer/industrialio-triggered-buffer.c
@@ -1,10 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-only
  /*
  * Copyright (c) 2012 Analog Devices, Inc.
  *  Author: Lars-Peter Clausen <lars@metafoo.de>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
  */
 
 #include <linux/kernel.h>
diff --git a/drivers/iio/buffer/kfifo_buf.c b/drivers/iio/buffer/kfifo_buf.c
index 70c302a..e78fc08 100644
--- a/drivers/iio/buffer/kfifo_buf.c
+++ b/drivers/iio/buffer/kfifo_buf.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 #include <linux/slab.h>
 #include <linux/kernel.h>
 #include <linux/module.h>